The invention relates to diagnosis and treatment of vascular injury.
In their normal state, vascular smooth muscle cells regulate vessel tone and blood pressure. Unlike skeletal muscle and cardiac muscle cells, these cells are not terminally differentiated. In response to mechanical, chemical, or immunologic injury (Libby et al., 1991, Lab Invest. 64:5-15; Munro et al., 1988, Lab Invest. 58:249-261; Ross, R., 1993, Nature 362:801-809; Tsai et al., 1994, Proc. Natl. Acad. Sci. U.S.A 91:6369-6373; and Tsai et al., 1996, Clin. Invest. 97:146-153), the phenotype of these cells changes rapidly from that of a differentiated, quiescent cell to that of a dedifferentiated, proliferating cell. Although vascular smooth muscle cell proliferation is a hallmark of arteriosclerosis, the leading cause of death in developed countries, little is known about the molecular mechanisms regulating this phenotypic change.